The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 17, 2018
Filed:
Mar. 21, 2017
Omnivision Technologies, Inc., Santa Clara, CA (US);
Chung-An Wang, Singapore, SG;
Dong Shi, Singapore, SG;
OmniVision Technologies, Inc., Santa Clara, CA (US);
Abstract
An echo canceller includes a fast Fourier transform (FFT) unit to provide frequency domain representation (FD) of an input. A multiband adaptive filter receives the FD of the input and provides an FD filter output, the adaptive filter is a finite input response (FIR) digital filter. Another FFT unit provides an FD of a microphone signal, and a summer adds the FD filter output to the FD of the microphone signal to provide echo-canceller FD output. A feedback subsystem uses the echo-canceller FD output to adjust filter coefficients of at least a first, a second, and a third frequency band of the multiband adaptive filter to minimize uncancelled output in the echo-canceller FD output. The feedback subsystem adjusts the filter coefficients of the second frequency band of the adaptive filter according to uncancelled output in the first, second, and third frequency bands of the echo-canceller FD output.